With continued miniaturization of semiconductor devices, there has been an increased demand for ultra-shallow junctions. For example, tremendous effort has been devoted to creating better activated, shallower and more abrupt source-drain extension junctions to meet the needs of modern semiconductor devices. It has been discovered that very low wafer temperature during ion implantation is advantageous for minimizing damage of a silicon wafer. In addition, there is an ongoing need for very low temperature cooling in a wide variety of other semiconductor processes and other fields.